When fired, the pulse gun suffers from a small delay before discharging, due to it building up the charge for the pulse. This results in the need to continue aiming on target after pulling the trigger to ensure a hit. As a weapon, the pulse gun is only effective against robots and power armor opponents, since it only delivers a small amount of impact damage otherwise.
Because of the amount of impact damage and the EMP bonus damage being constant, it is essentially unaffected by different ammunition types, perks, chems and energy weaponskill level. Additionally, the pulse gun is also ineffective against NCR salvaged power armor, mainly due to the fact that the armor has had all its joint servomotors removed and is no longer power armor in the traditional sense.
If the pulse gun is to be used frequently, bulk energy cells can be quite useful. The EMP effect isn't altered by the ammunition while the gun will take longer to break.
A single shot in Hardcore mode will use 0.39 pounds of ammunition, costing a combined value of 10 caps per shot.
The pulse gun uses 5 energy cells per blast, yet it's only possible to get a single empty energy cell from firing it, much like other energy weapons which use more than 1 cell per shot.
When aiming with true iron sights on, you will still have a crosshair.
The pulse gun is very similar in appearance and function to the Sonic Emitters from Old World Blues, both being anti-robot weapons. Cosmetically the only major differences are that the pulse gun lacks an oscilloscope, and uses more red in its finish. The pulse gun also deals far greater damage to robots than any of the sonic emitters without a critical hit. However, on a critical strike the Sonic emitter - robo-scorpion does nearly double the damage to power armor users and can roughly tie the pulse gun in damage dealt to robots. The Sonic emitters have a much higher base damage than the pulse gun making them feasible to fight non-robots and people not wearing power armor, where the pulse gun is nearly useless against non-machines.
Against robots specific to Old World Blues the pulse gun seems to use the Power Armor damage value rather than the robot damage value, making this weapon less potent than expected. This seems to apply to ALL Old World Blues specific robots, not just robo-scorpions. A possible explanation is given in the loading screen text of the Old World Blues, stating that robots in Big MT have additional EMP shielding to counter industrial espionage.